The present disclosed subject matter relates generally to locking mechanisms, and particularly to a pneumatic lock for a valve.
Bulk materials are often loaded and unloaded from a transport container, such as a tanker trailer, using a bottom loading adapter. The adapter contains a valve, and allows for a conduit, such as a hose, to connect to the transport container for transferring the material to and from the transport container. The materials involved may be relatively inert, caustic, or under high pressure. In addition, the material or environment may be of greatly different or extreme temperatures further complicating handling of the material and operation of the adapter and valve. Therefore, the design of the valve, and the materials used in construction and operation of the valve should accommodate varying materials and operating conditions.
Passage of the material through the adapter is controlled by a valve accessible at the exterior of the container. The easy accessibility of the valve lends them to unauthorized access and release of material from the transport container. Systems and methods for limiting access to the valves have been developed; however, their effectiveness is limited because they are difficult to use and may not be easily bypassed in an emergency to transfer the liquid material from the transport container.